title: Structure of the extended-spectrum β-lactamase TEM-72 inhibited by citrate.
abstract: TEM-72, a class A β-lactamase identified in isolates of Enterobacteriaceae, is a quadruple mutant of TEM-1 (Q39K, M182T, G238S and E240K) and shows extended-spectrum β-lactamase (ESBL) properties arising from the G238S and E240K substitutions. Although many structures of TEM variants have been published, they do not include an enzyme with the simultaneous presence of both of the ESBL-conferring G238S and E240K substitutions. Furthermore, the structure shows the presence of a citrate anion bound to the TEM-72 active site, where it interacts with all of the conserved residues of class A β-lactamases. The present structure supports the use of polycarboxylates as a scaffold for the design of broad-spectrum inhibitors of serine β-lactamases.
authors.affiliation: Dipartimento di Biologia Molecolare, Laboratorio di Fisiologia e Biotecnologia dei Microrganismi, Università di Siena, I-53100 Siena, Italy.
authors.forename: Jean Denis
authors.initials: JD
authors.lastname: Docquier
authors.forename: Manuela
authors.initials: M
authors.lastname: Benvenuti
authors.forename: Vito
authors.initials: V
authors.lastname: Calderone
authors.forename: Gian Maria
authors.initials: GM
authors.lastname: Rossolini
authors.forename: Stefano
authors.initials: S
authors.lastname: Mangani
mesh_terms: D019343:Citric Acid / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000737:chemistry* / Q000235:genetics
chemical_list: D065093:beta-Lactamase Inhibitors; D019343:Citric Acid; C413415:beta-lactamase TEM-72; D001618:beta-Lactamases